1. Technical Field
The present disclosure relates to a power supplying device, in particular, to a power supplying device having programmable current-balancing control.
2. Description of Related Art
Referring to FIG. 1, FIG. 1 is a circuit block diagram illustrating a conventional backup power supplying device. The backup power supplying device 1 comprises more than two power modules (11 and 12). FIG. 1 is an example of two power modules. Each of the power modules 11 (or 12) comprises a power convertor 111 (or 121), a current sensing component 112 (or 122), a current-balancing control circuit 113 (or 123), a switch 115 (or 125) and an output voltage controller 114 (or 124). In the conventional backup power supplying device 1, in order to jointly share the output power outputting to a load 13, there are at least two power modules for jointly providing the power needed by the load 13 in one system so that when any one of the power modules is interrupted abnormally, the other power module which can operate normally may keep provide power to the load 13 to meet the demand for uninterruptable power supply.
Based on active type current-balancing control, the current sensing component (112 or 122) senses the output current of the power module (11 or 12). A communicating wire 14 transmits the current-balancing voltage signal to the comparator circuit and the error amplifier circuit inside the current-balancing control circuit (113 or 123) of the other power module (12 or 11) for proceeding operation to get an amplifying gain value. The amplifying gain value is transmitted to the feedback end of the output voltage controller 114 to accomplish tuning voltage control. For example, a 100 ampere (A) system requiring load can be controlled by the current-balancing control circuits to accomplish 50%:50% ratio, which means the output current of each power module is 50 A.